DEC missed an enormous opportunity.
Source: I had one. You can see a pic here: https://twitter.com/WalterBright
The RT-11 operating system will look very familiar to anyone who used DOS or Windows.
https://en.wikipedia.org/wiki/Electronika_BK
Fun to ponder what would it be like if the PDP-11 (and descendents like VAX) architecture had become dominant instead of x86.
"...but it also requires at least a computer terminal and some form of storage to make it useful."
So what did you use for terminal and storage? Did you expand the memory beyond 4K?
The days of the kit-computer were on the way out when the triumvirate of Apple II/Commodore PET/TRS-80 Model I arrived in stores (unless you were handy with a soldering gun).
A bit later I bought a 6Mb hard drive, and designed and built an interface card for it and wrote the driver.
I put the Heathkit terminal, floppy drive, and cpu box together from their kits. They all worked the first try. (I paid part of my way through college soldering boards. Being able to solder well has paid off for me a lot over the years.)
The H11 was a bit pricey, but I wanted one real bad.
A couple of years later I put together a CP/M H89 but it never gave me that "real computer" feeling.
The software was professional and bulletproof. You could get real compilers for it, like FORTRAN. Compilers for the x86 took maybe a decade to reach that level.
The 8 bit computers of the day were toys next to it.
Of course, I was an idiot to develop software for the -11, as there was little market for it. The market was for the Apple and the IBM PC, and I eventually capitulated and bought a PC and abandoned the -11. Sob.